# Instructions

Table of Contents

This demo is a simple Airnode deployment, using a hands-on approach, to better understand the overall deployment process of the Airnode client image which deploys the off-chain component of Airnode (a.k.a., the node) to a Docker container, in this case a locally run Docker container. It uses an API endpoint (GET /simple/price) from CoinGecko (opens new window) which returns the current value of a coin. This demo does not detail the overall configuration of an Airnode, it is just a quick start.

An Airnode Docker container deployment uses a Docker image (called client image) which in turn requires two files as input.

For the purpose of this demo these files have been created and only require a few minor changes on your part to make the deployment of the demo Airnode successful. These changes are needed to supply a chain provider url and a mnemonic.

# Install Prerequisites

Install the Docker Desktop (opens new window) and launch it.

# Project Folder

A project folder is needed for this demo. You can create it manually or download a zip file ready to go.

# Configuration

Prepare the two configuration files, config.json and secrets.env. By default, the Airnode client image looks for them in the project root directory.

# config.json

This file requires no changes on your part. It has been created with just one API endpoint. It will instruct the Airnode to attach to the Rinkeby test network. There are a few variables this file will extract (interpolate) from secrets.env.

# secrets.env

Add values for each of the these fields.

CHAIN_PROVIDER_URL: A chain provider url from a provider such as Infura (opens new window). Make sure the provider url you use is for the Rinkeby test network. Using another chain provider other than Infura is acceptable.
- Sign-up or login to Infura.
- Create a new project, select the Settings tab in the project.
- Copy the URL (https) for Rinkeby under the Endpoints pick list.
AIRNODE_WALLET_MNEMONIC: Provide the seed phrase (mnemonic) to a digital wallet. For the purpose of this demo it does not need eth in it for the Rinkeby test network. If you don't have one use the Admin CLI command generate-airnode-mnemonic to create one or another method you prefer.
HTTP_GATEWAY_API_KEY: The authentication API key that needs to be sent with every HTTP gateway request.

# Deploy

Make sure Docker is running and then run the Airnode client container from the root of the quick-deploy-container folder.

Run the following command to deploy the Airnode locally. Note that the version of api3/airnode-client matches the nodeVersion in the config.json file.

Note that --publish HOST_PORT:CONTAINER_PORT parameter can have different values for the HOST_PORT and CONTAINER_PORT. E.g. parameter --publish 8000:3000 would expose the web server on port 8000 on the host machine. If run using host networking (opens new window) you need to change the port via gatewayServerPort property inside config.json.

For Linux, it's recommended to use host networking (opens new window).

# Test the Airnode

# Request

Make a CURL request using the example below. Be sure to replace HTTP_GATEWAY_API_KEY with your key from secrets.env.

# For Windows CMD replace line termination marker \ with ^
curl -X POST \
  -d '{"parameters":{"coinIds":"api3","coinVs_currencies":"usd"}}' \
  -H 'Content-Type: application/json' \
  -H 'x-api-key: <HTTP_GATEWAY_API_KEY>' \
  'http://localhost:3000/http-data/0x6db9e3e3d073ad12b66d28dd85bcf49f58577270b1cc2d48a43c7025f5c27af6'

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# Response

{
  "encodedValue": "0x0000000000000000000000000000000000000000000000000000000000362b30",
  "rawValue": { "api3": { "usd": 3.55 } },
  "values": ["3550000"]
}

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Note the JSON response values is the API3 price multiplied by 1e6, which results from setting the _times reserved parameter to 1000000 in config.json. This manipulation is necessary in order to correctly handle floating point numbers.

encodedValue: This is the only field that gets sent to a requester (smart contract) on-chain. It is the encoded bytes of the values field. A requester must decode it to read the response values.
rawValue: The API's response to Airnode. Presented by the HTTP gateway as a convenience. This is never sent to a requester on-chain.
values: A array of values after they are extracted and converted from the encodedValue to the target type, in this case api3.usd from _path in reservedParameters. The HTTP gateway provides this as a convenience and never sends the decoded values to a requester on-chain.

# Start and Stop

You can start and stop the Airnode with the Docker desktop application or via terminal commands.

docker stop quick-deploy-container-airnode
docker start quick-deploy-container-airnode

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# Logs

You can view the Airnode's logs with the Docker desktop application or via terminal commands.

docker logs quick-deploy-container-airnode
docker logs --follow quick-deploy-container-airnode

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# Remove the Airnode

When you are done with this demo you can remove it. Do so using the Docker desktop application or by using the following terminal command. When using the terminal command be sure to stop the container first if running.

# Stop the container if it is running.
docker stop quick-deploy-container-airnode
docker rm quick-deploy-container-airnode

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# Summary

You have deployed an Airnode into a Docker container. This Airnode attaches itself to the Rinkeby testnet as stated in the config.json file. The Airnode, upon deployment, started contacting the AirnodeRrpV0 contract on the Rinkeby testnet to gather any requests made by requesters to this Airnode.

This tutorial did not address making a request on-chain as its purpose was simply to quickly deploy a functional Airnode.

Finally the API integration was tested using the HTTP gateway. You made a CURL request (using HTTP) to the HTTP gateway and Airnode queried the API provider and sent back a response. All of this was performed without accessing the blockchain.

← Overview config.json →